|High-Speed Booster Track|
High-Speed Booster Rails are the high speed version of Powered Rail; they will boost cart speed to high speed if they are powered, and slow it down to normal speed if not powered. You may need several to get your cart up to full speed. Unlike transition rails, they are not one-way.
Maximum Speed on straight, level trackEdit
High-Speed Booster Rails appear to accelerate carts, empty or with a player inside, up to 20 blocks per second, whereas Powered Rails only accelerate carts up to 8 blocks per second.
It requires at least 15 High-Speed Booster Rails to accelerate a cart with a player inside from stopped to full speed, and at least 9 High-Speed Booster Rails to accelerate an empty cart from stopped to full speed.
In order to maintain maximum speed, at least 1 High-Speed Booster Rails must be placed and powered every 6 blocks, if a player is inside the cart, or every 7 blocks, if a player is not inside the cart.
It also requires at least 2 unpowered High-Speed Booster Rails to deccelerate a cart with a player inside from full speed to a slow enough speed to turn, transition onto other rails, or run out of track without an explosion. It requires at least 3 unpowered High-Speed Booster Rails to deccelerate an empty cart from full speed to a slow enough speed to turn, transition onto other rails, or run out of track without an explosion.
If you then want to re-accelerate to maximum speed after a turn, for example, it will require at least 7 High-Speed Booster Rails to reach maximum speed again whether or not you have a player in the cart.
Note: The above information involving maximum speed is the results of my experiments alone on High-Speed Booster Rails on a 200 block stretch. I used a timer to record the maximum times, 10.1 seconds, and how close I could get to that with as little rails as possible. I was about +/- .1 seconds off on these time trials. I feel they are accurate, but feel free to add a second perspective to this data, and update this paragraph when you do so.